:g/system:true/d
:g/'$syspreds'/d
:g/exit: system/d
:g/exit: lists/d
:g/call: system/d
:g/call: lists/d
:g/fail: system/d
:g/fail: lists/d

:g/root_subtrees/d
:g/look_rst_in/d
:g/is_list2/d
